Mechanical designer, better to have skill assessed?

[Petrus]

Hi all, I and my OH are applying for a 489 State Nominated Visa. The main applicant is my wife and then she already got her assessment.

I was wondering if assessing my skills too could be a good idea, in order to increase the possibility to get a job in my field.

As written above, I'm a mechanichal designer/draftsperson, with more than 15 years of experience, but I always worked here in Italy and even my educational qualifications have been released by Italian authorities.

In according with your Australian job experiences, are the overseas skills considered by the Aussie employers on the basis of a resume and a reference letter or not?

Is the skill assessment worth to be done even if I don't need it for the visa points?

I'm quite confused on it, since I often read that there in Oz you need a certification for every job you want to do... can anyone help me please?